Medicine and Health Sciences Commons^™

Anti-Apoptotic Mcl-1 Localizes To The Mitochondrial Matrix And Couples Mitochondrial Fusion To Respiration, Rhonda Perciavalle

Theses and Dissertations (ETD)

MCL-1, an anti-apoptotic BCL-2 family member that is essential for the survival of multiple cell lineages, is also among the most highly amplified genes in cancer. Although MCL-1 is known to oppose cell death, precisely how it functions to promote survival of normal and malignant cells is poorly understood. Here, I report that different forms of MCL-1 reside in distinct mitochondrial locations and exhibit separable functions. On the outer mitochondrial membrane, a MCL-1 isoform acts like other anti-apoptotic BCL-2 molecules to antagonize apoptosis, whereas an amino-terminally truncated isoform of MCL-1 that is imported into the mitochondrial matrix is necessary to …

Exogenous Alpha-Synuclein Induces Cell Death Related Proteins In C6 Oligodendrocyte-Like Cells Corresponding To Protein Expression Observed In Multiple System Atrophy, Derrick Samuel Hilton

Dissertations

Multiple System Atrophy (MSA) consists of three disorders; Autonomic Dysfunction, Cerebellar Ataxia, and Parkinsonism. In MSA, the protein Alpha-Synuclein (SNCA) appears in the central nervous system as misfolded protein aggregates primarily in oligodendrocytes. This dissertation reports the results from studies examining the effect of exogenous SNCA has on a cell model: C6 oligodendrocyte-like cells. Treated cells were evaluated using western blot and DNA microarray. In addition the expression of proteins was evaluated using immunocytochemistry in MSA patient tissue.

C6 cells were shown to take up SNCA when added to the media. SNCA also underwent a truncation when taken up by …

Function Of Insulin-Like Growth Factor Binding Protein 7 (Igfbp7) In Hepatocellular Carcinoma, Dong Chen

Theses and Dissertations

Title of Dissertation: FUNCTION OF INSULIN-LIKE GROWTH FACTOR BINDING PROTEIN 7(IGFBP7) IN HEPATOCELLULAR CARCINOMA By Dong Chen. Purpose: Hepatocellular carcinoma (HCC) is a highly virulent malignancy with no effective treatment, thus requiring the development of innovative and effective targeted therapies. The oncogene Astrocyte Elevated Gene-1 (AEG-1) plays a seminal role in hepatocarcinogenesis and profoundly downregulates Insulin-like Growth Factor Binding Protein-7 (IGFBP7). The present study focuses on analyzing potential tumor suppressor functions of IGFBP7 in HCC and the relevance of IGFBP7 downregulation in mediating AEG-1 function. Experimental Design: IGFBP7 expression was detected by immunohistochemistry in HCC tissue microarrays by real-time PCR …

Bim Mediates Imatinib-Induced Apoptosis Of Gastrointestinal Stromal Tumors: Translational Implications, David Reynoso

Dissertations & Theses (Open Access)

Gastrointestinal stromal tumors (GISTs) are oncogene-addicted cancers driven by activating mutations in the genes encoding receptor tyrosine kinases KIT and PDGFR-α. Imatinib mesylate, a specific inhibitor of KIT and PDGFR-α signaling, delays progression of GIST, but is incapable of achieving cure. Thus, most patients who initially respond to imatinib therapy eventually experience tumor progression, and have limited therapeutic options thereafter. To address imatinib-resistance and tumor progression, these studies sought to understand the molecular mechanisms that regulate apoptosis in GIST, and evaluate combination therapies that kill GISTs cells via complementary, but independent, mechanisms. BIM (Bcl-2 interacting mediator …

Preclinical Study Of Potential Antiglioma Novel Tetrahydroisoquinoline Analogs: Pharmacokinetics And Mechanism Of Action, Fei Ma

Theses and Dissertations (ETD)

Gliomas, the tumors of glial cells, account for 80% of primary malignant brain tumors. In 2011, there were about 18,300 new cases of maligant gliomas in the United States alone. Patients with glioblastoma multiforme or anaplastic astrocytoma, the two major types of malignant gliomas, have a median survival of 14 months or 2 to 3 years, respectively. Therefore novel treatments for malignant glioma are urgently needed.

A novel series of tetrahydroisoquinoline derivatives with antiglioma activity has been undergoing drug metabolism/pharmacokinetics (DMPK)-guided lead optimization. EDL-291 was result from structure modification of last generation compound EDL-155. Its preclinical pharmacokinetics were characterized in …

Evaluation Of The Role Of Oxidative Stress, Inflammation And Apoptosis In The Pulmonary And The Hepatic Toxicity Induced By Cerium Oxide Nanoparticles Following Intratracheal Instillation In Male Sprague-Dawley Rats, Siva Krishna Nalabotu

Theses, Dissertations and Capstones

The field of nanotechnology is rapidly progressing with potential applications in the automobile, healthcare, electronics, cosmetics, textiles, information technology, and environmental sectors. Nanomaterials are engineered structures with at least one dimension of 100 nanometers or less. With increased applications of nanotechnology, there are increased chances of exposure to manufactured nanomaterials. Recent reports on the toxicity of engineered nanomaterials have given scientific and regulatory agencies concerns over the safety of nanomaterials. Specifically, the Organization for Economic Co-operation and Development (OECD) has identified fourteen high priority nanomaterials for study. Cerium oxide (CeO2) nanoparticles are one among the high priority group. Recent data …

Proteasome Regulation Of Caspase-8: Significance In Cancer, Michael Vincent Fiandalo

Theses and Dissertations--Molecular and Cellular Biochemistry

Anti-tumor therapeutic strategies based on combinations of chemotherapeutic agents with a death inducing ligand such as TNF-α Related Apoptosis Inducing Ligand (TRAIL), are directed towards selective and effective cancer cell apoptosis and enhanced therapeutic response. We previously demonstrated that proteasome inhibition sensitizes TRAIL resistant prostate cancer cells to TRAIL-mediated apoptosis via stabilization of the active p18 subunit of initiator caspase-8. The present study investigated the functional link between caspase-8 and the proteasome, by analyzing the impact of caspase-8 ubiquitination and proteasomal degradation on the outcomes of the extrinsic apoptosis pathway in cancer cells. Caspase-8 ubiquitination status was assessed by polyubiquitin …

Hdm2 Small-Molecule Inhibitors For Therapeutic Intervention In B-Cell Lymphoma, Angela Sosin

Wayne State University Dissertations

Lymphomas frequently retain wild-type (wt) p53 function but overexpress HDM2, compromising p53 activity. Therefore, lymphoma is a suitable model for studying therapeutic value of disrupting HDM2-p53 association by small-molecule inhibitors (SMIs). HDM2 SMIs have been developed and are currently under various stages of preclinical and clinical investigation. This study examined various molecular mechanisms associated and biological effects of two different classes of HDM2 SMIs: the spiro-oxindoles (MI-219) and cis-imidazoline (Nutlin-3) in lymphoma cell lines and patient-derived B-lymphoma cells. Surprisingly, results revealed significant quantitative and qualitative differences between these two agents. At the molecular level, effect of Nutlin-3 was generally more …

The Role Of St6gal-I Sialylation In Fas (Cd95) Death Receptor Function And Tumorigenesis, Amanda F. Swindall

All ETDs from UAB

The golgi glycosyltransferase, ST6Gal-I, adds a negatively-charged sialic acid in an alpha-2-6 linkage to N-linked glycans. ST6Gal-I is upregulated in many cancers, and is associated with increased metastasis and poor patient prognosis. ST6Gal-I expression has been shown to be driven by oncogenic-ras signaling. However, mechanistic details of the role ST6Gal-I plays in tumor initiation and progression are not well defined. Historically, studies have focused on contributions of ST6Gal-I to the malignant cell phenotypes of migration and invasion. Emerging evidence including studies contained in this dissertation have begun to elucidate a role for ST6Gal-I as a regulator of apoptotic signaling by …

Regulation Of Cell Death By Autophagy In Glial Neoplasms, Latika R. Kohli

All ETDs from UAB

Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive malignancies of the peripheral nervous system. The majority of MPNSTs arise in patients of the autosomal dominant genetic disorder neurofibromatosis type I (NF1) although they also arise sporadically. In the absence of any effective chemotherapeutic options and with surgery constituting the mainstay of treatment, MPNST patients face an extremely poor prognosis. This underscores the need to develop novel therapeutic strategies against this tumor type. It is well accepted that the crosstalk between autophagy and apoptosis can be exploited to derive maximal therapeutic benefit, especially through combinatorial therapies. However, this interaction is extremely …

Regulation Of Neuronal Cell Death By Bh3-Only Proteins, Arindam P. Ghosh

All ETDs from UAB

Apoptosis in metazoan organisms plays critical roles in normal development, tissue homeostasis and immunity, and its disturbed regulation leads to many pathological states, including cancer, autoimmunity, infection and degenerative disorders. Apoptosis can be triggered by the engagement of `death receptors' of the tumor necrosis factor receptor family on the cell surface or by diverse intracellular signals that act upon the BCL2 (B-cell CLL/lymphoma 2) protein family, which controls the integrity of the mitochondrial outer membrane through the complex interactions of family members. Both the pathways lead to cellular demolition by dedicated proteases termed caspases. Different BH3-only proteins (or combinations of …